A member of an Einsatzgruppe prepares to shoot a Ukrainian Jew kneeling on the edge of a mass grave filled with bodies.

As the German army conquered territory to the east of Germany, they were followed by so-called Einsatzgruppen or killing squads. Their main task was to kill all Jews they encountered.

One of the most gruesome details of the Second World War was the history of the mobile killing squads. Their task was to kill Jews on the spot. But also communists, Gypsies, political leaders, and the intellectual elite were killed. There were about 600 to 1000 men in each Einsatzgruppe, although many were support staff.

The German army advanced very quickly to the east and most Jews, who tended to live in cities, were unaware of what was coming. Usually, the first step was to round up all the Jews in a certain area. Then they were marched to the forest and shot one by one. The victims would be buried in mass graves.

Sometimes, the killing squads did not even have to do the dirty work. Before they arrived, local residents had already taken the law into their own hands and decided to kill all the local Jews that they could find. This was especially the case in the small countries of Lithuania and Latvia. But most local residents decided not to take a stand at all, though they could hear the shots and screams in the distance.

In total, some 1.5 million men, women and children were murdered by the Einsatzgruppen.